Various cardiovascular procedures, such as angioplasty, stent placement and atherectomy, require gaining access to the vasculature. With reference to FIGS. 1 and 2, access to the vasculature of a patient typically is through the femoral artery and is percutaneous, involving insertion of a needle (not shown), and in some cases a dilator (not shown), in the region of the groin to form a track 103 through subcutaneous tissue T and to puncture and create an arteriotomy VA in a vessel wall VW of the femoral artery. A guidewire GW is then advanced through the needle and into the femoral artery. The needle and dilator, if present, are then removed. An introducer sheath 101, which is typically a single lumen catheter with a hemostasis valve on its proximal end, or other interventional device is then advanced over the guidewire GW, along the track 103 and into the femoral artery in order to perform the selected procedure. Introducer sheath 101 provides access into the femoral artery, through the arteriotomy, for longer guidewires, catheters or other instrumentalities in order to perform the selected procedure. The hemostasis valve on the introducer sheath is used to prevent extraneous bleed back or to introduce medication into the patient's body.
After the procedure has been completed, the interventional devices are removed and the arteriotomy must be closed. The size of the puncture opening in the artery corresponds to the size of the catheter or percutaneous introducer sheath used, and such devices may typically range in diameter from 5 French for a diagnostic procedure to 6-20 French for a therapeutic procedure. A number of techniques are known to facilitate closure and healing of the arteriotomy. One technique includes application of pressure at the puncture site for a relatively extended length of time. More particularly, compression has traditionally been applied to the puncture site for at least 30-45 minutes for the wound to close naturally after removal of the catheter. Patients are required to remain lying down, essentially motionless and often with a heavy sandbag placed on their upper leg, for several hours to ensure that the bleeding has stopped. The recovery time from the medical procedure may be as little as half of an hour, but the recovery time from the wound can exceed twenty-four hours. Longer recovery times may result in increased expenses, increased patient discomfort, and greater risk of complications. Other approaches to arteriotomy closure include a compression clamp device, a thrombotic or collagen plug, biological adhesives adapted to seal the arteriotomy, and/or stapling devices.
In addition, medical suturing systems have been proposed to facilitate closure and healing of the arteriotomy and resolve some of the concerns associated with arteriotomy closure after vascular catheterization procedures. In addition, beyond suturing devices utilized for closing arteriotomies, surgeons frequently encounter the need to close internal incisions, wounds, or otherwise joining tissue portions with a suture in situ. For example, FIG. 3 illustrates an incision 310 in the patient's skin used to perform a percutaneous or minimally invasive treatment on the patient. After the patient has been treated, a suture 312 is introduced into the patient through an introducer sheath 301 for the purpose of drawing together tissue portions 316, 318 (shown in phantom in FIG. 3). Two end portions 320, 322 of suture 312 extend from the tissue portions 316, 318, respectively, which may, for example, be the result of an internal wound or an arteriotomy in a blood vessel or an organ. Suture 312 may be introduced into the patient and positioned through tissue portions 316, 318 by any suitable manner or device, including but not limited to those described in U.S. Pat. No. 6,117,144 to Nobles et al., U.S. Pat. No. 6,562,052 to Nobles et al., U.S. Pat. No. 7,803,167 to Nobles et al., U.S. application Ser. No. 13/802,551 to Argentine, filed Mar. 13, 2013, and U.S. application Ser. No. 13/802,563 to Argentine, filed Mar. 13, 2013, all of which are hereby incorporated by reference in their entirety. Suture 312 is shown in FIG. 3 extending from catheter sheath introducer 301, but may alternatively extend directly from incision 310 in the patient.
After passing suture 312 through the tissue portions, i.e., after the suture has been positioned adjacent to the internal wound or arteriotomy, the two end portions 320, 322 of suture 312 must be tied or otherwise coupled together to draw the tissue portions together and prevent them from separating. The two end portions 320, 322 may be manually tied by the surgeon. However, sutures can often be difficult to handle and/or access, thereby increasing the procedure time. Thus, in some instances, surgeons prefer to use a device that secures or couples the two end portions of a suture in situ. For example, U.S. Pat. Nos. 8,197,497 and 8,469,975 to Nobles et al., which are assigned to the same assignee as the present application and are herein incorporated by reference in their entirety, describes a knot placement device that positions a knot or connector that secures or couples the two end portions of a suture in situ. The knot includes a knot body and a plug, and the knot placement device pushes a plug distally into the knot body and traps at least two suture portions between the plug and the knot body. The knot, i.e., the knot body and the plug, having the suture portions trapped therein may then be ejected out of the knot placement device. When ejected out of the knot placement device, the knot may be inadvertently pushed through the opening or arteriotomy of the treatment site. In addition to possibly losing or reducing hemostasis, if inadvertently pushed through the arteriotomy, the knot may contact and damage the inner vessel wall opposite the incision/arteriotomy.
Embodiments hereof relate to improvements of a device that secures or couples two or more suture portions.